function xmlhttp(url, method, postdata, additional_header)
{
	var http = new ActiveXObject("MSXML2.XMLHTTP");
	var head = "";
	var content = "";

	if (method == null)
	{
		method = "get";
	}

	method = method.toLowerCase();
	if (method != "get" && method != "post")
	{
		return Array(head, content);
	}

	http.Open(method, url, false);
	http.setRequestHeader("If-Modified-Since", "0");

	if (additional_header != null && additional_header != "")
	{
		var array = additional_header.split("&");
		for (n = 0; n < array.length; n++)
		{
			var key = ":";
			var index = array[n].indexOf(key);
			var name = array[n].substring(0, index);
			var value = array[n].substring(index + key.length, array[n].length);

			if (name != "")
			{
				http.setRequestHeader(name, value);
			}
		}
	}

	if (method == "post")
	{
		http.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
		http.Send(postdata);
	}
	else
	{
		http.Send();
	}

	head = http.getAllResponseHeaders();
	content = http.ResponseText;

	return Array(head, content);
}
